Centralize Zed.log documentation (#40808)

Just wanted a single location to point people to for telling them where
to find their log file. I left duplicate text in GitHub Issue templates,
as it seems annoying to have to follow a link when making an issue.

Release Notes:

- N/A

docs/src/SUMMARY.md

@@ -9,6 +9,7 @@
 - [Windows](./windows.md)
 - [Telemetry](./telemetry.md)
 - [Workspace Persistence](./workspace-persistence.md)
+- [Troubleshooting](./troubleshooting.md)
 - [Additional Learning Materials](./additional-learning-materials.md)
 
 # Configuration

docs/src/troubleshooting.md

@@ -0,0 +1,16 @@
+# Troubleshooting
+
+## Zed Log
+
+Often, a good first place to look when troubleshooting any issue in Zed is the Zed log, which might contain clues about what's going wrong.
+You can review the most recent 1000 lines of the log by running the {#action zed::OpenLog} command from the command palette (`cmd-shift-p` on macOS or `ctrl-shift-p` on Windows/Linux).
+If you want to view the full file, you can find it at the respective location on each operating system:
+
+- macOS: `~/Library/Logs/Zed/Zed.log`
+- Windows: `C:\Users\YOU\AppData\Local\Zed\logs\Zed.log`
+- Linux: `~/.local/share/zed/logs/Zed.log` or `$XDG_DATA_HOME`
+
+> Note: In some cases, it might be useful to monitor the log live, such as when [developing a Zed extension](https://zed.dev/docs/extensions/developing-extensions).
+> Example: `tail -f ~/Library/Logs/Zed/Zed.log`
+
+The log may contain enough context to help you debug the issue yourself, or you may find specific errors that are useful when filing a [GitHub Issue](https://github.com/zed-industries/zed/issues/new/choose) or when talking to Zed staff in our [Discord server](https://zed.dev/community-links#forums-and-discussions).